This invention relates to a pneumatically operated hoist comprising a housing provided with a suspension means for suspension of the hoist, in use thereof, from an overhead support, a pneumatically driven motor provided with a first flow passage arranged for serving as a pressurized air inlet during raising of a load and as an air exhaust passage during lowering of the load and a second flow passage arranged for serving as an air exhaust passage during raising of the load and a pressurized air inlet during lowering of the load, a load engaging means drivingly connected to the motor, and a control means for regulating air flow to and from the motor.
In known hoists of the above type it is not possible to provide both fast lowering for speed of operation which is permissible for light loads and slow and safe lowering required for heavy loads, as well as unrestricted load raising power under all load conditions.
It is an object of the present invention to provide a pneumatically operated hoist which overcomes or minimizes such disadvantages.